Disk-brakes have been known for a long time and conventionally comprise friction members received via their circumferential ends with anchoring and sliding on a member withstanding the braking torque, whether the latter consists of a fixed caliper, a sliding caliper or even a fixed support member, control means being associated in order to stress the friction member into braking contact with a corresponding face of the brake disk.
It is also known, for example from the document FR-A-2,330,916, to give the circumferential ends of the friction members a rounded surface capable of interacting with anchoring and sliding with a corresponding rounded surface defined on the torque-withstanding member, one of these rounded surfaces being concave and the other rounded surface being convex.
For a brake of this type, the document EP-B-0,002,399 makes provision for a friction member whose circumferential ends are received with sliding and anchoring on a torque-withstanding member, control means being associated with the latter in order to stress the friction member into braking contact with a corresponding face of a brake disk, at least a first of the circumferential ends of the friction member comprising at least one rounded surface capable of interacting with sliding and anchoring with a corresponding rounded surface defined on the torque-withstanding member, one of the rounded surfaces being concave, and the other rounded surface being convex, the radius of curvature of the convex surface being less than that of the concave surface, the friction member being received with a predetermined circumferential clearance in the torque-withstanding member, so that the friction member may occupy a first and a second extreme circumferential position corresponding to the friction member being anchored onto the torque-withstanding member via its first circumferential end or via the second circumferential end respectively, according to the direction of rotation of the disk, elastic means being provided in order to stress the friction member away from the first extreme circumferential position and into permanent contact with the rounded surface defined on the torque-withstanding member.
Such an arrangement has the object of forcing the friction member to move along an opposite surface defined on the torque-withstanding member each time the brake is actuated, so as to avoid the formation of deposits and automatically to scour the contacting rounded surfaces of the friction member and of the torque-withstanding member.